ATA_STD_QC_DEFER(9) libata Library ATA_STD_QC_DEFER(9)
NAME ata_std_qc_defer - Check whether a qc needs to be deferred
SYNOPSIS int ata_std_qc_defer(struct ata_queued_cmd * qc);
ARGUMENTS qc ATA command in question
DESCRIPTION Non-NCQ commands cannot run with any other command, NCQ or not. As upper layer only knows the queue depth, we are responsible for maintaining exclusion. This function checks whether a new command qc can be issued.
LOCKING spin_lock_irqsave(host lock)
RETURNS ATA_DEFER_* if deferring is needed, 0 otherwise.
AUTHOR Jeff Garzik Author.
COPYRIGHT Kernel Hackers Manual 2.6. July 2015 ATA_STD_QC_DEFER(9)